Increasing demands in medical treatment and animal husbandry draw a lot if attentions to efficient manipulation technology for in-vitro fertlization and cloning technology. This study is to develop an automated manipulation system for continuous cell operation. This paper described the concept of automated manipulation system and development of visual and force feedback systems as its core technologies.

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In the on-machine measurement, there are many merits in accuracy and efficiency because it is possible to measure a profile of various forms without attaching and removing the workpiece. Recently, many optical components with fine grooves, such as gratings of Fregnel lens, have been used, but it had been difficult to measure such profiles accurately. So the ultraprecision profile measuring probe with the fine stylus which enables a fine profile to be measured has been developed.

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Injection molding technology can replicate precise μm-wide structures such as a 1μm-pitch grating pattern. It cannnot, however, obtain precise mm-wide forms such as a fine flatness of 0.1μm / 10×10mm or a fine straightness of 1μm / 50mm because the mold cannot control physical phenomena of a plastic material in a cavity during processing cycle. Generally, injection molds do not have enough sensors / actuators to measure / coontrol the solidification process in each zone of the cavity. For example, plastic near an edge of the box replication solidifies quickly, causing a large bent at the center of the box. Moreover, the plastic is not uniform, creating a different characteristic during each cycle. We introduce a "smart palm-size injection mold", which has micro-sensors for pressure / temperature / displacement in the cavity zones and has piezo elements and heaters for controlling these parameters for each cycle. The target replica products are small, for example, an optical f-θ lens, a plastic-bonded hard magnet, a micro multi-pins connector and so on.

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A holographic grating was fabricated on a spherical surface using 5 axis ultrahigh precision machine tool. The fabrication of holographic grating have been carreid out with burnishing method. but it was not always possible to obtain deep blazed cross section or curved grooves. The authors here adopt ultraprecision cutting method with V-shaed single crystalline diamond cutting tool to overcome those limitations. A sample grating on a SR1000 sphere was successfully fabricated by this method.

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To improve the quality of cylindrical roller bearing, on of the most important factors is edge quality of the end of a roller. The authors already have presented the edge chamfering method by means of water jet in the previous paper. This paper presents the analytical study on the machining mechanism of the proposed method. The analysis is done based on abrasive distribution model within the jet acquired experimentally. The analysis has capability of predicting the machined geometry, taking relative distance and orientation between the workpiece and waterjet. The analytical results are proved by the experimental results.

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Prediction of contact between a grinding wheel and a workpiece is being required from production engineers. A prediction system of grinding-wheel contact was, therefore, developed employing the defused-laser detection from the trailing flow of grinding fluid. In this paper, the prediction system has been applied to grinding-wheel positioning. Trigger signal from the prediction system for stopping the wheel feed is sent to NC system when the diffused-laser intensity exceeds a certain level. Unevenness of the detected laser intensity results in the positioning error, which increases with the wheel-approach speed. Therefore, the trigger level is increased discretely with decrease of the wheel-approach speed. The wheel-positioning accuracy of the proposed system is 10 to 20μm.

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Not only the corrugation wear of railroad rail causes vibration and noise, but also it is mentioned as one of the factors which are connected with the derailment. As this corrugation wear countermeasure, the method that a cup grinding stone is installed in the vertical spindle and that it rotates, and that it does the re-profiling has been used. However, the problems that the grinding distance per unit time is short and that it is difficult to get a smooth plane, and that it is expensive, are also being taken up in this method. Then , in this study, the re-profiling equipment that facing contact polishing method with the ML belt was adopted has been developed. It is cheap and can carry out the high-precise and high-efficient re-profiling.

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Sapphire single crystals have been ground by the ultra-precision surface grinder with various cup-type resinoid-bonded diamond wheels of #400-#3000 in grain size. The relationship between the surface roughness and grinding conditions has been clarified in the ductile mode. The smooth surface of sapphire single crystal less than 1nm rms or 1nm Ra in surface roughness can be obtained by the ultra-precision grinding without any polishing process.

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We studied and tested porous vitrified-bonded diamond wheel with super fine grains (0-1/8μm). Polishing and lapping were currently employed in finishing process. There are some problems in worker's circumstance and abrasive grain cost, because a lot of free abrasive grains are used. We try to make grinding stones of super fine diamond abrasive that displace polishing and lapping grains. The pores faired chip exhaust and grinding lubricant flow. They provide pores by mixing pore agent in stone. The superfinishing process checked grinding performance of these grinding stones. The grinding performance of these stones is clarified for different bonds, pore agents and abrasive grains. We obtained superfinishing surface of nanometer-scale at Ra.

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CMP is concerning with the planarization technology which is contributing to high integration and multilayer wiring of LSI, but the polishing mechanism made by polishing agent manufactured by the sol-gel method has not completely made clear yet. In this paper, the polishing characteristic were examined experimentally, and we tried to investigate the mechanical and chemical action of the polishing slurry, based on the results by CMP for the work materials BK-7 and Cu. When the slurry is alkaline, silica particles are observed to adhere, and to deposit on the surface of the work BK-7. The material removal mechanism for CMP of Cu is concluded to be the processing mechanism that abrasives adhere to the work surface and the work material is removed together with abrasives by polishing cloth in atomic size.

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Recently, many kinds of abrasive tools using ultrafine grains are developed to mirrorfinish the surface. However, it is difficult to disperse the grains and the pores uniformly in such tool because of the aggregation peculiar to fineparticles. Therefore, the structure of agglomerates of three kinds of particle, grain, vitreous bond and organic substance has been discussed. The process used to generate the agglomerates is the diffusion-limited aggregation. As a consequence of the simulations, it has been found that the simulated agglomerate is similar in structure to the real one and the structure of agglomerates is affected by the component ratio.

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Fixed-abrasive multi-wire sawing process has been introduced by using a resinoind diamond wire tool or an electroplated diamond wire tool. Electroplated diamond wire tools have higher wear resistance, but the production cost is very high because the time required for electroplating in the manufacturing process is too long. Consequently, the tools cannot be applied to practical use. Then, ultra high-speed electroplating using a felt brush is proposed to adopt for manufacturing the tools in order to reduce the production cost. In this study, the effect of the electroplating factors, such as conductivity of abrasive, surfactant and shape of brush, on the amount of electrodeposited diamond grains was discussed. As a result, it was enable to change the amount and make the wire tool diameter uniform.

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We found that Spin On Glass (SOG) material acts as positive-type electron beam resist, and fine line pattern was obtained using electron beam exposure and following buffered HF development. Thus, SOG is the candidate material for high aspect ratio and fine pattern mask to organic materials such as polymethylmethacrylate (PMMA) by synchrotron radiation (SR) exposure. In this report, etching of PMMA by SR using SOG mask was examined. The SR, which emitted rom BL6 at the New SUBARU in Himeji Institute of technology, exposed to PMMA thorough SOG mask with fire patterns at room temperature. As a result, SOG mask layer was etched 263nm by SR and PMMA was etched 355nm by SR. Therefore, SOG was effective mask for PMMA, and this process would be able to do LIGA process without development.

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Laser trapping is a technology that uses laser to manipulate micro objects. We have carried out experiments on laser trapping of micro indeterminate object in water. Micro rod is one of the indeterminate objects. The experimental results show that it is possible to manipulate micro rod in two-dimensions freely and the micro rod can stand upright, rotate, and spin. Three-dimensional manipulations were also possible because of the irradiation from the lower side. It is thought that the rotation operation of the micro rod is useful as a driving source of micro stir element and the micro machine.

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In the harmonic generation using nonlinear optical crystals, it is well known that the frequency-conversion efficiency is very sensitive to temperature of the crystal, and decreases with irradiation time. In the previous study, we have investigated laser absorption dependence of SHG conversion efficiency theoretically with one-dimensional model, supposing uniform intensity beam. In this paper, two-dimensional analysis was carried out with an axisymmetrical model based on the previous one-dimensional model. The variation of the conversion efficiency of KDP crystal and the profile of output beam was analyzed quantitatively during repetition irradiation of pulse laser. Temperature control of the crystal was also applied theoretically, and its reduction effect for decline of conversion efficiency was investigated.

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This paper describes the frictional properties and the lubricating performances of the various fluids used in cutting being considered as environmental protection. As the frictional test method, the PIN-DISK method is employed, and the frictional coefficient is evaluated. In the frictional test, as the lubriants, the emulsion, the water and the synthetic detergent are used. The results are compared with the case of dry cutting without any fluid. As a result, we obtained that in most cases the frictional coefficients become smaller. Moreover, the surface roughness of workpiece is measured. The results show that the surface roughness is improved well.

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Cutting fluids used in metal cutting are sources of pollution and health hazards. Therefore, eco-machining such as dry cutting, minimum quantity lubrication (MQL), cold air cutting and etc. have been proposed. The purpose of this study is to show the suitable cutting conditions of eco-machining. So, itis necessary to clarify the effects of cutting temperature and cutting method on tool wear mechanism. In this paper, the effects of cutting conditions (cutting speed and feed rate) and coolant (air, cold air, water, wet) on cutting temperature and tool wear form have been investigated. It is concluded from the results that cold air cutting will be effective in cutting conditions with the cutting temperature of 800 degrees or less. And there is cooling capability of the same grade as the evaporation of water on cold air cutting.

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New grooving machine have been developed for cycle time up of high performance diesel engine bearings. This machine has been able to get better result for deeper and wider oil grooved bearings by a new cutting fluid supply system (Oil on water drop cutting fluid : OoW). This system consumes only 10mL/hour biodegradable oil and it is easy to recycle the cutting chips as well as the dry cutting system.

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Recently, it is necessary to reduce the amount of cutting fluids used in production lines in order to control environmental pollution. The logical step, which can be taken to avoid the environmental problem, is dry machining. However, dry machining is not always acceptable because of unfavorable manufacturing aspects such as decreased tool life and insufficient surface quality. To solve those problems, this study suggests minimal quantity lubrication (MQL) machining which is able to achieve both functions of cooling and lubrication of a cutting fluid and a large amount of air blow. This paper reports the effectiveness of the MQL system in the case of such continous machining as turning particularly when a biodegradable polyol ester is used as a cutting fluid. The lubricating action of this ester oil is also investigated in detail with the aid of surface analysis technics.

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This parer describes the cutting characteristics and economics of resharpened ball end mill. Original ball end mill made of cemented carbide and coated with (Ti, Al) N, and resharpened ball end mill are used in experiments. The workpiece is hot working tool steel. Its hardness is HRC43. Several machining characteristics, such as tool wear, chipping, and cutting forces were examined. The machining costs to the metal removal amount were compared. It became clear that 1) tool wear, chipping and cutting foeces of the original ball end mill are less than that of the resharpened one, 2) the use of the resharpened ball end mill is more economical.

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This paper presents and accurately estimating method for thermal deformation of machine tools. An exponential digital filter is used in this estimating method. In case of the thermal deformation arising from the rotation of main spindle, filter coefficient Fn is defined as a function which depends on the time constant and rotational speed. Besides the thermal deformation of machine structure arising from the change of room temperature is estimated in consideration of the time constant. Experimental results show efficiency of this proposed method.

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This report deals with a nanometer-cutting machine using Stewart platform type parallel mechanism. The movable range of the prototype is 20 μm in the x- and y- directions and 100 μm in the z- direction. The resonant frequency of the prototype is approximately 85 Hz in all directions. The stage motion was controlled by the displacement feedback control of the link length. The standard deviation of motion error was 0.1 μm after the calibration. This stage was applied to a positioning device of the nanometer-cutting machine. Pockets could be machined on acrylic resin with a vibration of the probe tip.

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This paper presents numerical solutions of static characteristics for a hybrid hydrostatic journal bearing which is able to change working fluid (air/water) according to load capacity. The numerical model considers misalignment of journal due to the offset loading. The Reynolds equation and the equilibrium equations of force and momentum were calculated simultaneously by the Newton-Raphson method. When the working fluid of the hybrid bearing was air, the shaft was declined in the loading direction and moves greatly. On other hand, When the fluid was water, the shaft was tilted in a direction perpendicular to the loading direction and traveled slightly in comparison with that in the air lubricated conditions.

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As a method to improve the stiffness of hydrostatic bearing, we proposed the new bearing structure in which the elastically supported land displaces for bearing clearance change instead of the shaft displacement. However, self-excited vibration occurred on this bearing within a certain operating condition. Then, the stable operable range was examined from both sides of analysis and experiment. The experimental results agreed with the tendency on the analytical result, in which assumed the damping of the land. In order to perform the stable operation under the optimum condition where attains nearly infinite stiffness, it is effective to decrease the rigidity of elastic body when load is small and to increase oil viscosity under large loading condition.

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We have developed Oiles Aerostatic Bearings (OABs) which have porous material that is mixed Cu-Ni based alloy with graphite powder and sintered. Compared with the conventional porous aerostatic bearings in which graphite and advanced ceramics are often used as porous material, OABs have following characteristics. 1) Flow rate [Nl/min] can be varied easier than usual. 2) It is possible to design comparatively various shapes of the bearings. 3) It is easier than usual to handle the bearings when setting because of graphite powder in the bearing surface. 4) Maximum dimensionless static stiffness of OABs shows 0.6-0.7. This paper presents porous material structure of OABs, and these bearings' static and dynamic characteristics.

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In this paper, we theoretically analyzed the non-repetitive run-out (NRRO) of rolling bearings used in machine tools caused by form errors of inner and outer races and rolling balls. It was recommended to use higher grade balls in order to reduce NRRO of rolling bearing used in machine tools. Diameter difference of balls in a bearing and even con-ponents of form error of balls are important factors to reduce NRRO.

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We developed a high speed spindle device, which can be attached to the main shaft of a machining center and can be used for high speed cutting with small tools. To keep precise and high speed rotation for long time, externally pressurized air bearing and shrink-fit-chuck was adopted. A prototype of the spindle device was tested and it rotates at 150,000(min)^<-1> continuously and stably. This paper outlines the structure of the prototype and result of evaluation test.

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To improve grinding machine performance with on-machine monitoring of working surface condition of grinding wheel, we had built up the on-machine measurement system of working surface profile with a laser micrometer. In this paper, the new method that is possible to monitor the complex change of the working surface conditions is proposed. To confirm the validity of the method, it was applied to mild steel grinding. It is made clear that monitoring the working surface condition based on the peak distributions of the profile makes it possible to evaluate four types of condition : deposition type loading, welding type loading, dulling and shedding.

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This paper presents machining process simulator for 2-1/2dimensional end milling processes. From an arbitrary NC program, the simulator extracts machining conditions that are not explicitly written in the NC program, such as the depth of cut, along the entire tool path. The cutting force is then simulated over the whole path based on the prediction model, which can be easily identified by conducting a set of pre-process machining tests. Furthermore, the process simulation can be straight forw ardly extended to the cutting force control. An intensive learning control method of cutting forces based on in-process updating of the simulation model is presented. The validity of the process simulation and the cutting force control method is verified in experimentation.

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This paper presents a method of real-time adaptive control of drilling and tapping for the difficult-to-cut materials such as superheat resistant alloy (Inconel718). Real-time adaptive control such as adaptive pecking is effective for these materials. In tapping process, normally adaptive control has disadvantage to be applied because C-axis requires high acceleration in the process. In general, conservative cutting speed is applied to such difficult-to-cut materials, since high cutting speed intense tool wear. Moreover, only in the case with low cutting speed, C-axis is able to be operated with high acceleration to stop its rotation. By introducing adaptive control, chip jamming is avoided during drilling and tapping process.

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It is important to reduce the run-out of the spindle for high speed machining centers due to the centrifugal force in order to get high machining performance. In this study, the balancing technique of the high-speed spindle is investigated. In the experiment, two displacement sensors are used to detect the run-out of the spindle and those outputs are analyzed through an FFT analyzer. The amplitude and phase of the run-out are measured. From these results, we can reduce both of run-out and vibration.

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There are some kinds of mathematical models of feed drive mechanism for machine tools. We modeled a feed drive mechanism by using the most popular model which is for two degrees of freedom, and proposed a simple friction model by considering the balance of the driving force and friction force. As a result of simulation using the model, the simulated circular trajectory was in agreement with the actual trajectory and the quadrant glitch was well expressed. However, the out put torque of the motor cannot be expressed in the simulation. In addition, the frequency response cannot be expressed with the parameters identified by the step response.

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OKUMA heralded in the industry and developed high-speed contour machining technology to control high-accuracy, high-quality and high-speed machining in shape machining as represented by die mold machining. In 1987,the technology was loaded into our company's computer numerical control "OSP". Since then, our company has developed and supplied a series of advanced control functions one after another prior to the needs of a market. OKUMA has developed the new high-speed contour machining technology "super-NURBS" which is based on technologies cultivated for many years. The new control technology "Super-NURBS" always pulls out the highest acceleration and deceleration performance of a machine also in curved surface machining. With this, "Super-NURBS" improves the machined accuracy and quality as well as reducing the machining time sharply (conventional ratio of our company twice). The following describes the abstracts and effects of new numerical control technology "Super-NURBS".

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Recently the high speed machining centers have been developed with the high lead ball screw systems or the linear motor systems. And higher cutting technology has been also developed. So the stick motions become worse as the advance of the high speed technology. The stick motions that happen in the circular motion damage the accuracy and the quality of work pieces extremely. In the conventional compensation system, it is need to tune the compensation parameters for each combination of radius and feed rate. In this research, a new stick motion compensation system is proposed. The new system has a dynamic model that simulates the friction system. And it is able to compensate the stick motions suitably for wide range conditions of radii and feed rates.

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